Lymph Node Ratio: A Novel Prognostic Indicator for Gastric Cancer

Introduction Gastric cancer remains one of the most common malignancies and is a leading cause of cancer-related mortality worldwide. Accurate nodal staging is critical for gastric cancer prognosis but is often compromised by "stage migration" and variability in lymph node (LN) harvest inherent in the current AJCC N-staging system. The lymph node ratio (LNR) has emerged as a potentially more reliable prognostic indicator that accounts for the extent of lymphadenectomy. This study aimed to evaluate the prognostic significance of the LNR, determine an optimal cutoff value, and compare its accuracy against the conventional AJCC 8th edition N-stage in patients undergoing curative gastrectomy. Methods and materials This was a single-institution, retrospective cohort study. The study analyzed 85 patients with non-metastatic gastric cancer who underwent surgical treatment between January 2021 and December 2024. Clinicopathological data were collected, and the LNR was calculated and categorized into four groups: LNR1 (0%), LNR2 (1-25%), LNR3 (26-50%), and LNR4 (51-100%). Results The median overall survival (OS) was 26 months. Only 24.7% of patients had an optimal LN dissection (>15 nodes). A higher LNR was strongly associated with poorer survival, with median OS decreasing from 36 months in LNR1 to 17 months in LNR4. Multivariate analysis revealed that LNR was a significant independent prognostic factor for survival (p<0.001), whereas the conventional pN stage was not (p=0.098). Conclusions The LNR is a simple, robust, and independent prognostic indicator for overall survival in patients with gastric cancer, appearing superior to the conventional pN stage. Its use can improve risk stratification, particularly in cases of suboptimal lymphadenectomy.